Corrosion costs the DoD billions of dollars annually and heavily impacts the availability of defense assets to carry out their missions. To maintain military readiness and reduce maintenance costs, the DoD protects weapons systems from corrosion using various surface engineering technologies. Historically, both corrosion mitigation and repair technologies have required hexavalent chromium, and other hazardous or toxic materials. SERDP and ESTCP are developing and demonstrating the science, tools, and techniques needed to meet critical defense performance criteria while also reducing the impact on the environment and protecting the health of DoD workers and military personnel.